Decreased Snow Cover in the Alps Threatens Europe’s Water Supplies

Hydrology and Earth System Sciences, 21 June 2022

Rising temperatures from continued high CO2 emissions may cut in half the number of days the Alps are covered in snow by the end of the century, jeopardizing seasonal water supplies for millions across much of Europe. The disappearance of the snow cover would be particularly harmful for communities relying on the water catchments in the southern Alps – including large regions of Italy, Slovenia, and France – that rely on spring and summer snow melt for freshwater. Under a high emissions scenario, these mid-altitude mountains could lose three months of their annual snow cover by 2100. If emissions are curbed to remain within the 1.5°C limit of the Paris Agreement however, more than three-quarters of current snow days and corresponding spring and summer water supplies would be saved. The retreat of the snow cover exposes the dark surface of the Alps to the sun, forcing the mountains to absorb heat more rapidly; this cycle creates a feedback loop that accelerates snow and ice loss across the Alps as emissions rise. Reduced water availability during the summer agricultural season poses an immense threat to communities that already experience water shortages. Authors underscore the importance of curbing global emissions to reduce future water strain on vulnerable downstream communities across much of Europe.

https://hess.copernicus.org/articles/26/3037/2022/